In a typical magnetic storage system, digital data is stored in a series of concentric circles or spiral tracks along a storage medium. Data is written to the medium by positioning a read/write head assembly over the medium at a selected location as the storage medium is rotated, and subsequently passing a modulated electric current through the head assembly such that a corresponding magnetic flux pattern is induced in the storage medium. To retrieve the stored data, the head assembly is positioned anew over the track as the storage medium is rotated. In this position, the previously stored magnetic flux pattern induces a current in the head assembly that can be converted to the previously recorded digital data. A servo control system is used to move the read/write head assembly across the storage medium as the medium is rotated, and may also control the rotation speed and therefore the frequency at which servo data is read. The read/write head assembly must be positioned correctly by the servo control system to properly read stored data. Patterns stored in various data fields of servo regions or servo wedges on the storage medium enable the servo control system to position the read/write head assembly. One such field is a position error signal (PES) burst field, typically grouped in four servo bursts that each include a series of transitions written at precise intervals and offsets from a data track centerline. The burst fields are demodulated and an analog peak detect is performed on the servo bursts to produce a position error signal indicating the direction in which the read/write head assembly should move to remain centered over the track. Flawscan is an important factory process to detect media defects, typically performed by detecting a signal field that has either a lower amplitude or larger channel metric, e.g., mean squared error compared to the ideal signal, than a pre-selected threshold. However, because the burst amplitude changes with respect to off-track position, flawscan is not supported in servo burst fields.